1. Field of the Invention
The invention relates generally to telephones and more particularly to a telephone unit with a programmable microprocessor which controls a speaker phone and the means for automatically forwarding calls to another telephone unit within a group of associated telephone units; said telephone unit including a status monitor means by which data is gathered by which the microprocessor determines the status of incoming telephone lines.
2. Description of the Prior Art
In the typical modern business setting, each member of an organization is likely to have a telephone, especially if the member is in a management or public contact position. These telephones are connected to the telephone communications system of the organization which in turn is connected to the system of the telephone company providing telephone service in the area. Thus, within the business there is an internal telephone communications system which receives outside calls and routes them to their proper destination within the organization, processes outgoing calls into the external telephone system for further routing by the telephone company, and permits intraorganizational communications over intercom lines which are usually part of the internal telephone communications system.
While some multi-line systems use key systems where each telephone has all of the outside lines serving the organization, larger internal telephone communications systems use a private branch exchange (PBX) to process incoming, outgoing, and intercom calls. Normally, a business is divided into various suborganizations or departments which may be further broken down by particular responsibilities or functions. Usually staff personnel are assigned to such suborganizations and among other responsibilities are assigned the task of receiving telephone calls for the various members of the suborganization. For simplicity of description, the staff person will be referred to as secretary and the organization members as executives. Under existing telephone communications system, several executives will have a common secretary. The executives usually have their own telephone and the secretary also has a telephone, all of which are interconnected either through the PBX or directly with each other. Depending upon individual desires or business requirements, it is desirable to control which telephone will ring and under what circumstances. Therefore, it is important to be able to coordinate the ring arrangement of the various telephone units. Existing systems are fixed in the changes which can be made to the ringing arrangement.
One of the fixed ring arrangements currently in use is the "duplicate ringing" system where the telephone at the executive and secretarial stations both ring. Usually the secretary is instructed to allow the telephone to ring two or three times to permit the executive an opportunity to answer. After the specified number of rings the secretary will answer the telephone. This setup creates several problems. Where the secretary serves more than one executive, the secretary may be confronted with multiple lines ringing at the same time requiring counting of rings for each, resulting in confusing and potential missed calls or interruption of an executive who has already answered. The "duplicate ringing" system can also cause an inconvenience for the executive. For example, if the executive does not desire to answer because of involvement in a conference with others or other work, the executive still must suffer the specified number of rings interrupting the conference or concentration before the secretary will answer.
Another fixed system currently available is the "delayed ringing" system which is an attempt to eliminate some of the problems associated with the "duplicate ringing" system described above. When a call comes in to a "delayed ringing" system, the executive's phone rings first (the secretary's telephone does not ring at this point). After the specified number of rings (e.g., two or three) the secretary's telephone begins to ring while the executive telephone continues to ring. The ringing of the secretary's telephone indicates that the executive does not desire to answer the call and that the secretary should answer it. This eliminates a need for the secretary to count rings before answering but does nothing to end the interruption to the executive when in conference.
A third fixed system existing in the prior art is an "overflow ringing" system. This is used in a situation where the executive has more than one telephone line. When the executive is using one telephone line and a call comes in on one of the other telephone lines, the additional call will ring at the secretarial station.
Another fixed system is "primary line screening". An executive having two telephone lines can give out the number of one line to a limited number of people to whom the executive wants to speak directly without screening by the secretary. The number of the other line is given to those whose calls the executive desires to have screened. Thus, calls coming in on the first line will ring at the executive station and can be answered directly by the executive. Calls coming in on the second line will ring only at the secretarial station where they can be answered and screened by the secretary.
In an attempt to overcome some of the problems with such ringing arrangements, some telephone systems have a "do not disturb" feature in the PBX. By entering a code involving several keystrokes into the PBX, no calls will be received at the station activating the "do not disturb" feature. However, if an urgent call must be put through, the executive must first disable the "do not disturb" function by entering several keystrokes before being able to receive the call. This is awkward and time consuming and as a result the feature tends not to be used.
Another feature sometimes available is a "call forwarding" function. This permits an executive to have calls forwarded to another number. Again this feature as contained in the PBX requires between five and nine keystrokes per activation or deactivation. Like the "do not disturb" feature, "call forwarding" is slow and cumbersome to use. An example of a telephone containing various call transferring features which are controlled by a microprocessor is discussed in U.S. Pat. No. 4,298,775 issued to Norman R. Buck, et al.
Speakerphones are well known in the art. Generally, the speakerphone permits only one way communication, switching between transmit and receive depending on which party is speaking the loudest. None of the existing speakerphones use microprocessors contained in the telephone set to control the audio path switching of the speakerphone. As a result, more hardware is needed for the speakerphone, ease of manufacture is reduced and no consideration is given to the relative normal volume of the voices of the parties to a speakerphone conversation.